Refrigerated goods case



Feb. 2, 1960 s. v. SWANSON REFRIGERATED GOODS CASE Filed Feb. 12, 1958 2 Sheets-Sheet 1.

INVENTOR.

5m??? U fizz/amam BY g REFRIGERATED GOODS CASE es Paten Sven V. Swanson, Niles, Mich., assignor to Tyler Refrig- I eration Corporation, Niles, Mich., a corporation of Michigan Application February 12, 1958, Serial N0.714,900

12 Claims. (Cl. 62-256) My invention relates to refrigerated food and beverage cases, and more particularly to cases or cabinets of the class noted, having utility in merchandising perishable products primarily in self-service stores.

The need for refrigeration to prevent spoilage of many foods is, of course, Well known and the food processing art in its present development continues with the creation of many new products requiring refrigeration from the time of their preparation or packaging by the food processors or distributors until they reach the hands of the consumer. To this end, two types of cases are employed primarily by self-service stores to receive and maintain food and beverage products under refrigeration and to render the goods available for display and selection by the customer. One such case, hereinafter referred to as a horizontal case, is in the form of a tank type receptacle open at its top, and the storage area below the open top is charged with cold air from suitable refrigeration apparatus. Since the cold air is heavier than the surrounding warmer room air, the heat gain in the storage area is kept to a minimum suitable for economic operation. The second form of case, hereinafter referred to as a vertical case, fundamentally takes the form of a completely enclosed chamber and is usually provided with a plurality of horizontally extending shelves on which the goods are supported for display and storage, and to which access is had through an opening in the front wall of the case, the opening and closing of which is effected by means of transparent access doors which may be conventionally vertically hinged, or sliding access doors arranged for sliding movement in vertical planes in trackways at the top and bottom edges of an opening in the front wall of the case or cabinet.

The aforementioned refrigerated cases have many disadvantages and limitations in use both to the customer and seller. In the first mentioned horizontal case, the goods are loaded through the open top and are arranged in layers or are stacked in superposed relation. The loading aforementioned is inconvenient, the display of different goods stacked within the case is at a minimum, and, in fact, many items may be completely covered by others so that a customer is not even aware that a particular commodity is available. Additionally, many refrigerated goods to be edible and palatable must be consumed within a given period of time, and since such cases provide little ready visual inspection without shifting or removing the goods, the retailer must frequently examine the stock at considerable inconvenience and remove those items which are no longer safely salable. Additionally, in cases of the type last noted, it is inconvenient for the customer to reach down into the storage area to select and remove the desired goods, and to the retailer, the operation is equally difiicult in stocking the cases, and such inconvenience for the retailer is compounded when a case is to be cleaned.

In the aforementioned vertical cases, a major disadvantage lies in the fact that hinged access doors must be opened and closed by the customer in making a selection of goods, and such doors may readily cause accidents by careless use. Further, frequent opening and closing of the doors causes excessive condensation of moisture on the glass panels or access doors, as well as the goods, and the shelves and packaged goods are unattractive for display and handling purposes.

In both the aforementioned horizontal and vertical cases, loading of goods for sale is generally accomplished through the same opening through which the goods are removed by the customer with the attendant disadvantages of interference of the store personnel and customers whose activities are thus carried on in the same area of the store. Goods to be dispensed in both kinds of cases is, of course, in many instances delivered under refrigeration to the retail store. Upon delivery of such goods they should obviously be immediately stocked in the cases. Frequently such operation cannot immediately be accomplished and, of course, many disadvantages result. Food may spoil, the useful life of goods requiring refrigeration may be shortened, and rerefrigeration may be necessary which, of course, taxes the refrigerating capacity of the unit. To overcome certain of the last enumerated problems storage coolers are conventionally provided to accommodate perishable goods before the latter are placed in the sales cases. By this device, however, multiple handling operations of the goods are required and the cost factor there involved may readily make the store operation unprofitable.

It is an object of my present invention toprovide refrigerated goods cases which avoid all of the aforementioned and other disadvantages of known refrigerated cases and which may be easily and economically constructed and operated.

It is a further object of my invention to provide refrigeratd goods cases having substantially unobstructed access openings in the front walls thereof, and a plurality of superposed horizontally extending goods supporting members arranged in vertical spaced relation in the case, rearwardly of the access openings therein, and in which the access openings are spanned by refrigerated air barriers between the access openings and the goods supporting members.

A further object of my invention is to provide refrigerated cases as last noted in which there are refrigerated storage areas in juxtaposition of the goods supporting members.

A further objectof my invention is to provide a refrigerated case as last noted having door or closure means between the goods supporting members and the aforementioned refrigerated storage area.

A further object of my invention is to provide a refrigerated case as last noted comprising means affording access to the refrigerated storage area rearwardly of the goods supporting members.

A further object of my invention is to provide a novel refrigerated air barrier for the access opening in the front wall of a'refrigerated case to afford an efficient and effective barrier between the air outside the case and the refrigerated interior of the case.

A further object is to provide novel means affording a novel refrigerated air barrier to effectively and efliciently set apart a refrigerated area from the Surrounding atmosphere.

. In order to achieve the aforementioned objects, I propose, in a preferred embodiment of my invention, to provide an enclosed case which maybe of any desired dimension for suitable use for display and dispensing of refrigerated goods having its enclosing walls and panels Or other like planar members built, in the conventional manner, for refrigeration purposes with the exception that a wall thereof, for example, the front wall is provided with an access opening through which goods are 2,923,137 3 d removed by the customers from the case. Within the bled off refrigerated air to secondary reinforcing insulatcase, rearwardly of the access opening in the aforementioned wall thereof, there is arranged a plurality of food supporting members, which may be solid on perforated shelves, or formed of wire or otherwise, as the character of the foods to be supported and displayed thereon require. The food supporting members or shelves extend horizontally, and are arranged in superposed vertical spaced relation for the goods to be carried thereby, and in position so that a person by reaching through the access opening may readily and conveniently remove the goods desired. In such arrangement, my invention further comprehends the creation of a refrigerated air barrier traversing the opening from bottom to top to maintain effectively the goods on the support members or shelves under appropriate refrigeration.

Additionally, if desired, the case of my invention, by appropriate dimensioning thereof, maycomprise a refrigerated storage area, in addition to the display and dispensing area afforded by the goods supporting members or shelves, in juxtaposition of the latter so as to keep close at hand appropriate quantities of goods for replenishing of the supporting members or shelves as the goods are removed therefrom by customers through the access opening in the front wall of the case. It is preferable, although not necessary, that suitable doors, such as sliding doors be arranged between the rear of the goods supporting members or shelves and the refrigerated storage area so that stock clerks, when the supporting members or shelves are depleted, may replenish them from stock in the storage area, through such doors. It is, of course, appropriate to provide one of the Walls of the case with a door for access to the re frigerated storage area.

Additionally, if desired, a side or rear wall of the case may be provided with door means opening outwardly of the wall of the store building, in which a case of my invention is arranged, so that delivery of refrigerated goods from a refrigerated truck may be moved directly into the storage area of the case.

It will be readily comprehended that refrigerated goods cases constructed in accordance with the aforementioned objects avoid all of the above enumerated disadvanatges of present day refrigerated cases, and the refrigerated cases of my invention possess many new and unique advantages as already related, or as will become clear as the description of my invention proceeds.

There are, in addition to the above objects of my invention, new unique and structural features, and relationships of refrigeration parameters.

First, in this regard, the aforementioned refrigerated air barrier of my invention comprehends critical ranges of certain variable parameters to aiford an efiicient and economical insulating barrier involving, for reasons to be fully discussed hereinafter, the vertical height for the front wall access opening, a range of relative velocities of refrigerated air for spanning the opening, and a range of temperatures for the refrigerated air of the air barrier.

Secondary, but important features concern the location of means through which the refrigerated air for the air barrier is discharged at the base of the front Wall.

access opening, and location of return opening means for the refrigerated air at the upper portion of the case.

A further preferred feature resides in a novel refrigerated air circuit for effecting the refrigerated air barrier including an arrangement of air cooling coils and air impellers.

A still further preferred feature resides in unique proportioning of widths of the goods supporting members or shelves to avoid undue turbulence of refrigerated air within the case.

Astill further preferred feature has to do with novel means for preventing the developing of substantial static pressure in the refrigerated storage area of, the case, by'

bleeding off refrigerated air therefrom, and utilizing the ing purposes in association with the aforementioned refrigerated air barrier.

The above and other objects, advantages, and features of my invention will appear from the following detailed description of a preferred embodiment of my invention.

Now in order to acquaint those skilled in the art with the manner of constructing and utilizing refrigerated cases in accordance with my invention, I shall describe in connection with the accompanying drawings, a preferred embodiment of my invention.

"In the drawings:

Figure 1 is a perspective view looking toward the front and one side wall of a case constructed in accordance with the principles of my invention;

Figure 2 is a longitudinal vertical cross-sectional view of the case shown in Figure 1, taken along the line 2-2 of Figure 3 looking in the direction indicated by arrows;

Figure 3 is a transverse cross-sectional view of the case of Figure 1, taken along the line 33 of Figure 2 looking in the direction indicated by the arrows; and

Figure 4 is a diagrammatic illustration of the refrigeration circuit embodied in the case shown in Figures 1 through 3.

Referring now to the drawings, I have shown my invention embodied in an enclosed refrigerated case comprising, front and rear wails 4 and 5, respectively, top and bottom walls 6 and 7, respectively, and side walls '8 and 9 respectively. The right hand side wall 9, as shown in Figure 1 of the drawings, has been broken away to show the relationship of certain of the parts at the front of the refrigerated case of the embodiment of my invention herein disclosed. The several Walls and panel members of the illustrated case of my invention are largely diagrammatically shown in that they may be constructed in accordance with conventional practices presently followed in building refrigerated cases or cabinets, and the front wall and other of the walls may be provided with decorative sheet panel members or the like as may be desired.

An important aspect of the refrigerated case of my present invention resides in providing a substantially unobstructed access opening 11, preferably in the front wall of the case, and as will be hereinafter more particularly related, the opening 11 may conveniently be of a vertical height in a range of from about 3 ft to about 5 ft. The width or longitudinal extent of the access opening is not critical, and its dimension is dictated solely by the length desired for the case.

In the preferred form of the refrigerated case of my invention, there is provided a longitudinally extending partition or bulk head 13, which extends parallel with and intermediate of the front and rear walls 4- and 5 to divide the easing into what may be termed a display and dispensing area, indicated generally at 14, to which access may be had by customers through opening 11, and a refrigerated storage area, indicated generally at 15.

As shown, side wall 9 of the refrigerated case may, for example, be provided with a hinged door 16 providing access for store personnel to the refrigerated area 15, and back wall 5, as indicated in dotted lines at 17 may have provision made therein for a door or opening v17 so that when the case is mounted with the back wall thereof against a door or delivery opening in the outside wall of the store or building in which the case is to be employed, may provide access for delivery of goods, for example, from a refrigerated truck directly into the refrigerated storage area 15, in accordance with the aforementioned object of my invention in that regard. It will be readily apparent, however, that the location of door 16 and of door or opening 17 may be varied to suit the requirements of a particular installation of the case in a store or elsewhere.

It will be observed upon reference particularly to Figures 2 and 3, that head assemblies indicated generally at A and B are incorporated in the lower and upper end portions of the display and dispensing area 14, respectively, and extend longitudinally of the case between side walls is and 9. The lower head assembly A comprises, a plenum chamber 18 defined by suitably shaped and spaced apart sheet metal panels 21 and 22 arranged to provide a fan chamber 23 which is in communication with the refrigerated storage area through an opening centrally of the lower end of the intermediate partition 13. An air impeller 24 of conventional fan type and an electric motor 25 therefor may be conveniently arranged in fan chamber 23. In the reduced throat portion 26 between panels 21 and 22, there is arranged an elongated refrigerated cooling coil 27 through which air passing thereto is caused to be cooled. From the discharge side of the cooling coil 27, a longitudinally extending vertical sheet metal panel 30 is spaced inwardly from the adjacent inside surface of the lower portion of the front wall 4 to provide an air discharge slot 32, extending substantially the full length of the case between side walls 8 and 9, and providing for the discharge of refrigerated air through a longitudinally extending throat 33 at the upper end of the slot 32. The throat 33 is defined by an angularly inwardly and upwardly extending guide surface 34 at the upper inner longitudinal edge of the lower portion of front wall 4 defining the lower limit of access opening 11. Air discharged through the throat 33, as shown, flows upwardly and inwardly and traverses access opening 11 in traveling to upper head assembly B. It is to be understood that such flow of air, for purposes of this invention, constitutes the air barrier referred to and claimed herein. The upper head assembly B comprises a horizontally disposed longitudinally extending sheet panel member 35 and which defines a ceiling or upper closure for the display and dispensing area 14. The inner edge portion of the sheet metal member 35 is provided with a plurality of longitudinal slots or openings 36 through which the air discharged through the aforementioned throat 33 flows into a chamber 37 appropriately formed by sheet metal members 38 and 39, and between which a second refrigerating coil.40 is disposed. Air entering opening 36 is drawn into plenum chamber 41 by a pair of fans 42, which may, like fan 24, be of the propeller type, driven by the armature shafts of electric motors 43. As will be seen, the plenum chamber 41 is constituted by suitable sheet metal planar members 44 and 45, and the upper portion of partition 13 to provide an enclosure so that the fans 42 are effective to draw the air entering the ports or slots 36 through the refrigerating coil into the plenum chamber 41 from whence the air is discharged into the refrigerated storage area, generally indicated at 15, through fan openings 46 suitably formed in partition 13. The air thus discharged by the fans 42 may, if the unit requires additional refrigerating capacity, pass through a third cooling coil of conventional and known construction diagrammatically shown at 50, in the upper rearward portion of the refrigerated storage area.15. -For convenience, the refrigerated storage area.

15 may, if desired, be furnished with shelving or storage racks, as indicated at 52, for the storage of goods under refrigeration, and which is to be displayed and dispensed to customers via display and dispensing area 14.

Refer-ring again-to the display and dispensing area 14, inthe form of the invention herein shown, we provide abottom supporting sheet metal plate member 55 extendinghorizontally and longitudinally of the case upon which goodsto be dispensed may be supported. A'pluwhich are guided in upper and lower trackways 63 and 64, respectively. The doors may be opened from the refrigerated storage area 15 to provide access to the shelves 56, 57, and 58 and bottom plate member 55 for the transfer of goods from the refrigerated storage area 15 to the display and dispensing area 14 of the refriger ated case.

It is significant in my invention that the uppermost shelf 58 be of a width not in excess of the width of any of the shelves there below for reasons to follow in connection with the provision of an effective air barrier, afforded by the aforedescribed air path between discharge throat 33 and return slots 36 to maintain the display and dispensing area 14 under appropriate refrigeration, and in proper insulated relation to the surrounding room air outside the case. The shelf arrangement may, as shown, for example in Figure 3 comprise shelves 57 and 58 of equal width, and the lower shelf 56 being of substantially greater width. If desired, the intermediate shelf 57 may be of the same width as lower shelf 56 but in any event, the uppermost shelf 58 should not ex ceed the width of any of the other shelves, and preferably should be of less width than the maximum width of any shelf below the latter.

As shown in Figure 1, the shelves 56, 57, and 58 need not be continuous from end to end, and in refrigerated cases of substantial length it may, in fact, be preferable to provide such shelving in contiguous but separate sections for convenience in removal for cleaning purposes, or otherwise. For example, as shown in Figure 1 section 57a of shelf 57 may constitute a simple flat planar member for the disposal of packaged goods thereon, whereas section 5712 of shelf 57 may be perforated, if in connection with the goods stored thereon, circulation of air about the entire periphery of the package is desirable or required. It will be appreciated that the shelves may be mounted in any conventional and known manner in the display and dispensing area 14, and such shelves, if desired, may be angled downwardly toward access opening 11 also by known conventional means for that purpose. 7

It will be clear in the construction above described that goods stored in the storage area 15 may be conveniently loaded on the goods or food supporting members 55 through 58 by opening of the sliding doors 60 and simply stacking the goods on the several supporting members. It is equally obvious that the goods may be readily removed by customers reaching through the refrigerated air barrier flowing upwardly from the bottom edge of the access opening 11 and removing the goods from the shelves. As noted the access opening 11 is substantially unobstructed from top to bottom, and end to end, so that the goods are effectively displayed on the goods supporting shelves and the customer may readily see and remove the desired product. Additionally, if desired, and as shown in Figure 3, a conventional light source may be arranged to project downwardly from the upper longitudinal edge of the access opening 11 as typically shown at 65, with the light source being disposed behind a suitable sheet metal shield 62.

The pair of fans 42 of the upper head assembly B are of acapacity in excess of that of fan 24 of the lower head assembly A and in order to avoid creating static pressure in the-refrigerated store area 15, the upper edge portion of partition 13 is providedwith a series of bores or openings 70, opening into the equal-- izing channel 71 formed by the sheet metal member 44 and the adjacent inside upper surface of top Wall 6.

The channel 71 thus formed is in communication with a chamber 72 formed between the sheet metal member 45 andthe inside surface of the upper portion of front -wall member 4 from which the bled off air -is. dis-.

charged through a plurality of longitudinally extending slots 73 in theforward edge portion of sheet metal plate 35 im mediately adjacent the upper edge of the ac 7 cess opening 11 so as to provide an air stream, as indicated by the arrows on Figure 3, to prevent the influx of warm air along-the upper longitudinal extent of the access opening 11.

Referring now to Figure 4, I have shown diagrammatically the refrigeration circuit incorporated in the aforedescribed refrigerator case. The several refrigeration coils previously described, namely, coils 27, 4 0, and 50 are shown as having conventional connection each with an expansion valve 75 which in turn are commonly connected by a common liquid line 76 to the receiver reservoir 78. The several coils also have connection with a common suction line 7? having connection with a conventional compressor 80 which, in turn, has connection with any suitable condenser 81. The condenser 81 may, for example, be air cooled by means of a power driven fan 82. The motor for the several fans 24, 42 and 82 as well as light source 60, may be connected with a source of electrical energy in a conventional manner, and in view of expedients for so doing is common knowledge such circuitry has been omitted;

In the aforedescribed case construction, in order to provide an effective refrigerated air barrier, operable at an economical refrigeration capacity, the following parameters and the ranges therefor, as stated, below are deemed to be important.

Firstly, the access opening 11 should be of a vertical extent or height in the range of from about 3 ft. to about 5 ft. The range noted denotes the vertical dimension of a convenient access opening adequately providing for display of the goods on the goods supporting members 55, 56, 57, and 58 and for the convenient reaching-in and withdrawal of goods from the goods supporting members. The disposition of the bottom of the access opening from the floor line is not critical, but obviously should be at a height convenient for disposal of the lowermost goods supporting shelf so that customers may reach in and conveniently remove the goods. The maximum height of the opening also should be disposed at sufiicient distance vertically above the goods on the uppermost shelf 58 of the case with the latter being again at a convenient height so that a customer may conveniently and without due upward reaching, have access to the goods thereon. The aforementioned range of vertical dimension for the reach-in opening also bears important relationship to the hereinafter discussed air velocities and refrigerated air temperatures of the air barrier for the access opening 11 and as will'be appreciated, are related to this aforementioned range of about three to about five feet.

The longitudinal extent or length of the access opening 11 is not critical and may be of an appropriate dimension suitable to the length of the case. It will, of course, be understood that the refrigeration capacity of the refrigerating assembly described in connection with Figure 4 is related to the total cubic capacity of the display and dispensing area 14, and refrigerated area 15 to maintain a desired temperature range within the refrigerated case. Thus the refrigeration ton requirement 7 for the refrigerated case is dependent upon the. temperature to be maintained within the case and its overall cubic content. With the determination of these last mentioned variable factors, the following ranges of parameters are applicable in all instances. 7

An important parameter for the aforesaid access opening to provide an effective air barrier resides in the discharge velocity of the refrigerated air at the longitudinally extending throat or slot 33 extending lengthwise at the upper edge of the bottom portion of front wall 4 and defining the lower edge of access opening 11. I have found that the refrigerated air should be discharged at a velocity in a range of from about 350 to about 550 feet per minute. The low end. of the range aforementioned is critical in that it is essential that the cold refrigerated air within the case beprevented of the upper head assembly B and the adjacent portion of the dividing partition 13.

from its natural tendency to spill out along the bottom edge of the opening as would be the case if that natural tendency was not countered by the upward discharge of refrigerated air through the throat 33. The upper end of the aforementioned velocity range is deemed important, in that refrigerated air moving at a velocity substantially in excess thereof, will create undue turbulence causing mixing in of the warm room air from outside the access opening 11. At velocities markedly in excess of 550 feet per minute, would require an undue increase in refrigeration capacity for the case and render it too costly for profitable operation.

A still further important parameter resides in the temperature of the refrigerated air discharged at the discharge slot or throat 33. The refrigerated air discharged should lie ina differential range of from about 8 F. to about 15 F. below the temperature to be maintained within the refrigerated case. If such differential is less than 8 F. then the desired inside temperature of the case will not be maintained, for example, if the temperature desired to be maintained at the shelves is 38 F., then the temperature of the'refrigerated air at the discharge slot 33 should preferably not be higher than 30 F. Air at temperatures within the aforesaid differential range of temperature provides for wiping of radiant heat from products on the shelves, and also is sutficient to attend to latent heat diffused from the surrounding air into the cooler. The upper limit of the aforementioned differential range, namely 15 F., would in the aforementioned example of a desired 38 temperature within the refrigerated case, require that the air discharged at throat 33 be not lower than 23 F. Refrigerated air at te r; peratures markedly less than 23 F., inthe aforesaid example, would not be necessary in order to maintain the temperature in area 14, nor desirable from an economic point of view as the lower air temperature requires a lower refrigeration temperature, which, in turn, requires higher power input for the same refrigeration etfect.

Secondary, but other important aspects to provide for efiicient operation of the refrigerated case resides in the width of the slot 33 through which the air is discharged. I have found that preferably the width should lie in a range of from about a minimum of /8 to about a maximum of 1%"; In order to maintain an acceptable uniformity of temperature in area 14, the movement of a predetermined volume of air is required. With a throat opening less than A" the velocity in discharging such quantity of air would be so great that the increased turbulence would increase the refrigeration load appreciably. With the. throat wider than about 1%" the velocity in discharging such quantity of air is too low to eifectively stop the natural tendency to spill out along the bottom edge of the opening 11. Increasing the velocity to prevent such spilling would unduly increase the volume of air handled by the apparatus with resultant increase in the refrigeration load. Also, in regard to the discharge slot or throat 33, it should be directed at an angle inwardly and upwardly on a line extending in a direction toward the return slots 36 of the upper header assembly B so as to impart an upwardly and rearwardly direction to the air barrier. It is preferable, as aforedescribed, that the return slots 36 be disposed adjacent the rear edge of the bottom planar member 35 upper Also, as previously mentioned, it is preferable that the uppermost shelf 58 be of a width so as not to project unduly into the refrigerated air barrier for access opening 11 to prevent undue turbulence and disruption of the flow of the air of the air barrier in its travel from the discharge throat 33 to the return slots or ports 36. While the upper shelf 58 should be of relatively narrow width for the purpose indicated, it is apparent that the intermediate shelf 57 or the bottom shelf, 56 may be of greater width if desired than the upper shelf and not interfere with the refrigerated air barrier.

In a case constructed in accordance with my invention, the aforementioned parameters existed in a case in which the access opening measured 3 /2 ft. in height by 8 ft. in width. The cubic capacity of the case totaled 600 cubic ft. of which the display and dispensing area 14 comprised 100 cubic ft. and the refrigerated storage area 15 comprised 430 cubic ft. and the remaining volume being occupied by the aforedescribed components of the case. Operating within the aforementioned parameters a shelf temperature of approximately 38 F., was maintained with a refrigeration capacity of between 1% to 1% tons with the refrigerating system described in connection with Figure 4. A case of like construction, but without the refrigerated air barrier, .to maintain the aforementioned exemplary temperature of 38 F. at the shelves, would require in excess of on an order of 16 tons refrigeration.

It will be understood, of course, that the aforementioned values have to do with the customary conditions prevalent in the usual or normal store installation in which, since the advent of air conditioning, the normal room temperature will be in the vicinity of 80 F. and 50% relative humidity.

While I have shown what I consider to be a preferred embodiment of my invention, it will be understood that various modifications and rearrangements may be made therein without departing from the spirit and scope of the invention.

I claim:

l. A case of the class described comprising, front and rear walls, partition means parallel with and intermediate said front and rear walls dividing said case into a display and dispensing area and a storage area, said front wall having an opening therein, a plurality of horizontally extending goods supporting members mounted in superposed spaced vertical relation within said display and dispensing area, said goods supporting members being accessible through said opening in said front wall, door means in said partition means for aifording access to said goods supporting members from said storage area, a lower head assembly in said display and dispensing area between the lower portion of said front wall and said partition means below said opening in said front wall, an upper head assembly in said display and dispensing area between said front wall and said partition above the opening in said front wall, air refrigerating means in each of said lower and upper head assemblies, air propelling means in each of said lower and upper head assemblies-between said display and dispensing area and said storage area, air discharge throat means below said opening at said front wall in communication with said lower head assembly, return air means above said opening in said front wall in communication with said upper head assembly adjacent said partition means, and said air impellers affording circulation of air between said display and dispensing area and said storage area through said refrigerating means and upwardly through said discharge throat means and into said air return means to provide an air barrier traversing the opening in said front wall.

2. A case of the class described comprising, front and rear Walls, partition means parallel with and intermediate said front and rear walls dividing said case into a display and dispensing area and .a storage area, said front wall having an opening therein, a plurality of horizontally extending goods supporting members mounted in superposed spaced vertical relation within ,said display and dispensing area, said goods supporting members being accessible through said opening in said front wall, door means in said partition means for affording access to said goods supporting members from said storage area, a lower head assembly in said display and dispensing area between the lower portion of said front wall and said partition means below said opening in said front wall, an upper head assembly in said display and dispensing area between said frcnt wall and said partition above the opening in said front wall, air refrigerating means in each of said lower and upper head assemblies, air propelling means in each of said lower and upper head assemblies between said display and dispensing area and said storage area, said air propelling means in said upper head assembly being of greater capacity than the air propelling means in said lower head assembly, air discharge throat means below said opening at said front wall in communication with said lower head assembly, return air means above said opening in said front wall in communication with said upper head assembly adjacent said partition means, and passageway means in said upper head assembly extending between the upper end of said storage area to the upper edge of said opening in said front wall to prevent static pressure in said storage area and prevent the influx of surrounding air outside the said case along the upper edge of said opening.

3. The case of claim 1 characterized by the opening in the front wall thereof being of a vertical height in a range of fromabout 3 feet to about 5 feet, the velocity of the discharged air from said throat means for said air barrier being in the range of from about 350 feet per minute to about 550 feet per minute, the temperature of the discharged air at the bottom of said opening being in a differential range of from about 8 F. to 15 F. less than a predetermined temperature to be maintained at said goods supporting members, and said throat means being of a width of from about inch to 1% inches.

4. The case of claim 1 characterized by the provision of air refrigerating means in said storage area.

5. The caseof claim 1 characterized by the provision of door means in a wall thereof affording access to said storage area. r

6. The case of claim 1 characterized by the uppermost goods supporting member being of a width not in excess of the widths of the goods supporting members therebelow.

7. A case of the class described comprising front and rear walls, partition means intermediate said front and rear walls dividing said case into a display and dispens ing area and a storage area, said front wall having an access opening therein, a pair of head assemblies connecting the upper and lower end portions of said display and dispensing area and said storage area with each other through said partition means, air discharge opening means i in one of said head assemblies adjacent said access opening of said front wall, air return opening means in the other of said head assemblies, a plurality of horizontally extending goods supporting members mounted in superposed spaced vertical relation within said display and dispensing area and lying between said air discharge opening means and said air return opening means of said head assemblies, air impeller means for effecting circulation of air in acircuitous path between said display and dispensing area and said storage area and from said air discharge opening means to said air return means to provide an air barrier traversing said access opening in said front wall inwardly of the latter, air refrigerating means in. said circuitous path of air, and said partition means having opening means affording access to said goods supporting members in said display and dispensing area from said storage area. t I

.8. A case of the class described comprising front and rear walls, partition means intermediate said front and rear walls dividing saidcase into a display and dispensing area and a storage area, said front wall having an access opening therein, pair of head assemblies connecting the upper and lower end portions of said display and dispensing area and said storage area with each other through said partition means, air discharge opening means in one of said head assemblies adjacent said access opening of said front wall, air return opening means in the other of said head assemblies, a plurality of horizontally extending goods supporting members mounted in superposed spaced vertical relation within said display and dispensing area and lying between said air discharge opening means and said air return opening means of said head assemblies, the goods supporting member of said plurality of goods supporting members in closest proximity to said air return opening means being of a width less than the width of the goods supporting member in closest proximity to said air discharge opening means, air impeller means for effecting circulation of air in a circuitous path between said display and dispensing area and said storage area and from said air discharge opening means to said air return means to provide an air barrier traversing said access opening in said front wall inwardly of the latter, air refrigerating means in said circuitous path of air, and said partition menas having opening means affording access to said goods supporting members in said display and dispensing area from said storage area.

9. A case of the class described comprising front and rear walls, partition means intermediate said front and rear walls dividing said case into a display and dispensing area and a storage area, said front wall having an access opening therein, a pair of head assemblies connecting the upper and lower end portions of said display and dispensing area and said storage area with each other through said partition means, air discharge opening means in one of said head assemblies adjacent said access opening of said front wall, air return opening means in the other of said head assemblies, a plurality of horizontally extending goods supporting members mounted in superposed spaced vertical relation within said display and dispensing area and lying between said air discharge opening means and said air return opening means of said head assemblies, said access opening in said front wall being of a height in excess of the overall vertical height of said plurality of goods supporting members, air impeller means for effecting circulation of air in a circuitous path between said display and dispensing area and said storage area and from said air discharge opening means to said air return means to provide an air barrier traversing said access opening in said front wall inwardly of the latter, air refrigerating means in said circuitous path of air, and said partition means having opening means affording access to said goods supporting members in said display and dispensing area from said storage area.

it). A case of the class described comprising front and rear Walls, partition means intermediate said front and rear walls dividing said case into a display and dispensing area and a storage area, said front wall having an access opening therein, a pair of head assemblies connecting the upper and lower end portions of said display and dispensing area and said storage area with each other through said partition means, air discharge opening means in one of said head assemblies adjacent said access opening of said front wall, air return opening means in the other of said head assemblies, a plurality of horizontally extending goods supporting members mounted in superposed spaced vertical relation within said display and dispensing area and lying between said air discharge opening means and said air. return opening means of said head assemblies, air impeller means for effecting circulation of air in a circuitous path between said display and dispensing area and said storage area and from said air discharge opening means to said air return means to provide an air barrier traversing said access opening in said front wall inwardly of the latter, air refrigerating means in said circuitous path of air, said partition means having opening means affording access to said goods supporting members in said display and dispensing area from said storage area, and passageway means extending between said storage area and said display and dispensing area to prevent the building up of static air pressure in said storage compartment.

ii. A case of the class described comprising front and rear walls, partition means intermediate said front and rear walls dividing said case into a display and dispensing area and a storage area, said front wall having an access opening therein, a lower head assembly including a plenum chamber below said access opening connecting the lower end portions of said display and dispensing area and said storage area with each other through said partition means, an upper head assembly including a plenum chamber above said access opening connecting upper end portions of said display and dispensing area and said storage area with each other through said partition means, air discharge opening means in one of said plenum chambers adjacent said access opening of said front wall, air return opening means in the other of said plenum chamhers, air impeller means in each of said upper and lower plenum chambers for inducing flow of air in a circuitous path between display and dispensing area and said storage area, and from said air discharge opening means to said air return means to provide an air barrier traversing said access opening in said front wall inwardly of the latter, air refrigerating means in said circuitous path for refrigerating the air in the same, and said partition means having opening means affording access to said goods supporting members in said display and dispensing area from said storage area.

12. A case of the class described comprising front and rear walls, partition means intermediate said front and rear walls dividing said case into a display and dispensing area and a storage area, said front wall having an access opening therein, a plurality of horizontally extending goods supporting members mounted in superposed spaced vertical relation within said display and dispensing area and having their rear edges lying adjacent said partition means, a lower head assembly including a plenum chamber disposed below said goods supporting members and connecting the lower end portions of said display and dispensing area and said storage area with each other through said partition means, an upper head assembly including a plenum chamber above said goods supporting members and connecting upper end portions of said display and dispensing area and said storage area with each other through said partition means, air impeller means in each of said upper and lower plenum chambers for inducing flow of air in a circuitous path between said display and dispensing area and said storage area and from said air discharge opening means to said air return means to provide an air barrier traversing said access opening in said front wall inwardly of the latter, air refrigerating means in each of said plenum chambers for refrigerating the air in said circuitous path, said partition means having opening means affording access to said goods supporting members in said display and dispensing area from said storage area, and passageway means for said upper plenum chamber extending from said storage area to said display and dispensing area to prevent the building up of static air pressure in said storage chamber.

References Cited in the file of this patent UNITED STATES PATENTS Weber May 27, 1958 

